Earlier the perf test runner using CPC was broken. This change fixes that.

With this change, we will be running CPC a little different than what we used to.
Earlier, we run CPC for 'n' of iterations and the first iteration should to be a
warmup iteration. Each iteration runs all the tests once.

Now, we run CPC for 'n' iterations for each test and 'n' is defined by each test.
The first iteration is, again, a warmup iteration and the rest are considered for the
metrics calculation. With this model, each iteration will run just one test instead of
running all the tests in an iteration. This helps in making the warmup iteration, a
true warmup iteration.

Minor changes:
Since the test csx returns an object now, the test related information has been
moved to the corresponding test csx files.

In the absence of the CPC tool and other related tools that help in
producing metrics, the user should be able to run the tests and get some
basic metrics.

This placement is temporary. We will later introduce flags whether to
run the msbuild on Roslyn, to download CPC.

This code to work we need the patched CPC with the changes from
basoundr/CPCChangeToWorkWithPerf_3_21

Some code cleanup

Enable the tools that were included to run

This change expects all the tests to be under the Tests folder under the
Perf folder

and some refactorings

Add classes to help run CPC

- build.csx (fetches the latest source and produces a build for testing)
- fetch_build.csx (fetches the latest signed build for testing)
- install.csx (installs the binaries you built or fetched, backing up your
  currently installed binaries)
- uninstall.csx (restores previously installed binaries from backup)